Whirring sound when in gear

[Raisinbrain]

2015 1500 Big Horn crew cab, 5.7 gas, 8HP70 4x4, 99,800 miles.

About 10k miles ago I had both differentials, transfer case, transmission fluid, and pan changed (New OEM pan, and recommended fluids for all).

I began noticing a whirring sound that was a little harsher on occasion. This sound would only show up when the truck was fully warmed up, in gear, and after driving.

The sound was most noticeable at low speeds, e.g. 0-5 MPH, and would go away if shifted into Neutral or Park.

The transmission fluid level was checked at (Aamco) and they said the transmission was not making a sound that wasn't typical.

There are no signs of leaks. Engine and Transmission temps are normal

One last note: If I shift to neutral and back into gear, the noise stops until the next time I drive.

Does anyone know what could be going on?

 

[RamInfo]

When AAMCO checked the fluid level, did they do it with the rear of the truck jacked up until the trans-to-pan mating surface was level both ways? And start with a cold trans, following the proper procedure posted in multiple places in this forum?




Best,
RI

 

[Raisinbrain]

Thank you for your reply RI. I'm not sure if Aamco checked the fluid level properly. I know the transmission was warm when they assessed it, and frankly, they didn't have the truck in the bay long enough to follow the recommended procedure you sent me.

Since the fluid and pan were changed nearly a year ago, everything was working fine until recently. That being said, I'm wondering where the initial fluid level may have gone. No leaks were seen.

???

 

[CanuckRam1313]

I'd be going to a shop that WILL FOLLOW the above directions to a T.

If the fluid looks or smells out of sorts, I'd take a sample and send it to Blackstone, or another lab for analysis.
I'd also change the fluid and filter if there is any indication that the existing fluid could be an issue.